textproduct: Albany

WHAT HAS CHANGED

Increased POPs across the western Adirondacks, western Mohawk Valley and southern Greens through early Tuesday morning to account for incoming lake effect snow showers.

KEY MESSAGES

1. West to northwest wind gusts reaching 35 to 50 mph through early this morning may lead to some downed tree limbs and isolated power outages.

2. Seasonably mild temperatures Tuesday and Wednesday before a pattern change towards the end of the week results in colder temperatures and an increasing potential for snowfall as two systems interact. Latest probabilistic guidance shows there is a 15 to 35% chance for 4 inches or more of snow between 7AM Thurs and 7AM Fri.

DISCUSSION

KEY MESSAGE 1...

Cold advection in the wake of our departing upper level trough continues to promote deep mixing tonight with the latest ASOS and NYS mesonet observation showing maximum wind gusts up to 40 to 50mph in the Capital District into western MA. The strongest winds will occur through 09-10 UTC (5/6AM) before winds decrease below advisory criteria(< 46 mph) around or shortly after sunrise this morning. The wind advisory is in effect through 9 AM but if winds weaken enough hand, we may need to cancel it early. Westerly winds remain breezy through the day today reaching 20-30 mph but weaken through the afternoon.

KEY MESSAGE 2...

Zonal flow today through early Tuesday will maintain lake effect snow showers in Herkimer/Hamilton Counties. A shortwave embedded within the westerly flow this evening looks to strengthen the lake effect signal with snow showers expanding into the western Mohawk Valley and upslope showers developing over the southern Greens. An additional 1 to 3 inches of snow is expected with up to 4-6" north of Route 28 in northern Herkimer). While slippery travel conditions are possible tonight, will hold off on an advisory for northern Herkimer County given the areas where over 4" is expected is remote.

Temperatures trend milder Tuesday into Wednesday as a shortwave trough amplifies over the Great Lakes, inducing southwesterly flow over the Northeast. Forecast confidence remains low to medium for the Wednesday to Friday period as this parent trough continues to dig and potentially phase with additional southern stream shortwaves rounding its base. While there is increasing good agreement in phasing occurring, the timing remains a bit uncertain which will play an important role on where its cold front stalls and where any developing coastal low tracks. There is better agreement among the latest GEFS, GEPS, and ECMWF ensembles that now suggest the phasing occurs a little too far west and therefore any coastal low that develops Thursday into Friday tracks further out to sea thereby keeping impacts over eastern NY and western New England low.

Even though the potential for impacts from any coastal low have trended downwards, confidence in impacts from the cold front associated with the parent cyclone Wed night through Thurs night have increased. As the parent cyclone phases with southern stream shortwaves and intensifies, the baroclincity across the cold front strengthens thereby increasing the coverage and intensity of developing showers Wed night through Thurs night. In fact, guidance also shows signs of a secondary low developing along the boundary, increasing precipitation coverage/intensity even further. We therefore continue to message widespread chance to likely POPs Wed night through Thurs night with precipitation trending to mainly snow between diabatic cooling processes and colder air sweeping into the Northeast behind the boundary. Latest snowfall probabilities from the NBM show 30-60% for 2 inches or more of snow from 7AM Thurs to 7AM Fri with 15-35% for 4 inches or more of snow across much of eastern NY and western New England. This could result in slippery travel Thursday into Friday.

AVIATION /06Z MONDAY THROUGH FRIDAY/

We start the TAF period with a mix of MVFR and VFR conditions due to low cloud ceilings. MVFR conditions become VFR near 12z when the low cloud ceilings gradually improve at KPSF. For KALB, MVFR conditions can periodically occur as ceilings fluctuate between VFR and MVFR through 10z. Otherwise, VFR conditions continue through the TAF period. Gusty winds between 35 and 50 knots continue for KPSF through this morning when winds gradually decrease this afternoon to less than 35 knots. For KPOU and KGFL, winds continue to be breezy between 15 and 25 knots through this afternoon. For KALB, gusty winds between 25 and 35 knots continue through this morning. Westerly winds decrease to less than 25 knots this afternoon and change direction to the southwest.

Outlook...

Tuesday Night: Moderate Operational Impact. Chance of RA. Wednesday: Moderate Operational Impact. Likely RA. Wednesday Night: High Operational Impact. Likely RA...SN. Thursday: High Operational Impact. Likely SN. Thursday Night: Moderate Operational Impact. Chance of SN. Friday: Low Operational Impact. Slight Chance of SN. Friday Night: No Operational Impact. NO SIG WX. Saturday: Low Operational Impact. Slight Chance of SN.

ALY WATCHES/WARNINGS/ADVISORIES

CT...None. NY...Wind Advisory until 9 AM EST this morning for NYZ038>041- 047>054-058>061-082. MA...Wind Advisory until 9 AM EST this morning for MAZ001-025. VT...None.